Yarn clamping and cutting means and method for knitting machines



Oct. 31, 1961 F. R. SHOAF 3,006,173

YARN CLAMPING AND CUTTING MEANS AND METHOD FOR KNITTING MACHINES Filed March 27, 1956 3 Sheets-Sheet 1 Y T 105 03 27 I02 i 1 25 w as 82 Z3 ,7- -45 lo! I 2.2 37 i aucTIoN rHO ll u Souwze INVENTOR; FLOYD R. SHQAF BY $41M, $5M +2.11

' ATTORNEYS F. R. SHOAF Oct. 31, 1961 YARN CLAMPING AND CUTTING MEANS AND METHOD FOR KNITTING MACHINES 5 Sheets-Sheet 2 Filed March 27, 1956 N H M a M H Q W m w +0; Nb wm m L F ATTORNEYS F. R. SHOAF 3,006,173

YARN CLAMPING AND CUTTING MEANS AND METHOD FOR KNITTING MACHINES Oct. 31, 1961 Filed March 2?. 1956 3 Sheets-Sheet 5 INVENTOR How 12. SHOAF.

ATTORNEYS 3,006,173 Patented Oct. 31, 1961 ice 3,006,173 YARN CLAMPING AND QUITENG MEAN AND METHQD FOR KNITTING IVEACHE ES Floyd R. Shoat, 674 S. Union St, Concord, Nfll. Filed Mar. 27, 1956, Ser. No. 574,168 30 Claims. or. 66-140) This invention relates to circular knitting machines and,

more especially, to an improved method of and means for clamping and severing yarn closely adjacent the needles.

As is well known in the art, circular knitting machines are provided with rotary series of needles adjacent which one or more yarn feeding stations are disposed and each yarn feeding station generally includes a plurality of yarn feed fingers which are moved into operative position for feeding yarn to the needles in predetermined sequence in accordance with the desired pattern. At times, only a single yarn feed finger occupies operative position and, at other times, two or more yarn feed fingers may occupy operative position. Many such knitting machines, particularly such as are used in the knitting of ladies seamless hosiery, are equipped with a dial having dial needles which cooperate with cylinder needles in knitting double fabric, mock-rib tops and the like.

As each yarn feed finger on a machine of the type indicated is raised to inoperative position, a relatively long end of yarn extends from each yarn feed finger sowithdrawn from operative position, which yarn end is clamped by a clamping means positioned upon a clamp and cutter support plate or dial. As each yarn feed finger subsequently returns to operative position, the corresponding relatively long yarn end remains loose in the fabric and forms a long yarn tail of such length that it is necessary to subsequently manually sever the yarn.

It is an object of this invention to provide an im' proved means for and method of severing yarn on a circular knitting machine wherein, upon any yarn finger being moved to inactive position, the yarn is severed closely adjacent the needles and clamped and, with subsequent movement of the latter finger to active position, a few stitches are knit from the corresponding yarn to form a yarn tail extending from the initial needle to which the yarn was fed to the clamping means, which yarn tail is also severed closely adjacent the needles.

It is another object of this invention to provide an improved yarn clamping and cutting means which will automatically sever the in-going and out-going yarn fed by any one or more of the yarn feed fingers at points more closely adjacent the needles than has been possible heretofore during the knitting operation, thereby obviating the necessity of subsequently severing the yarn tails.

It is another object of this invention to provide suction means for clearing the unattached residual yarn ends, resulting from severing both the in-going and out-going yarn, from the zone of the yarn clamping and cutting means.

It is another object of this invention to provide an arcuate clamp and cutter plate .or disk, which may be embodied in the usual dial cam cap, positioned in substantially axial alinement with the needle cylinder and above the level of the sinkers or web holders and Whose peripheral edge is provided with at least one outwardly projecting cutter blade disposed closely adjacent the path of raised cylinder needles or, in the instance of a dial mechanism being used, immediately above the dial bits or dial needles, with means for guiding the in-going yarn inwardly against the periphery of the disk and, thus into engagement with the cutter blade at a point subsequent to the knitting zone or stitch-forming Zone whereby the 2 in-going yarn is severed closely adjacent the needles, regardless of whether they be dial needles or cylinder needles. The cutting device also functions in the same manner to sever the out-going yarn as the corresponding yarn feed finger is raised to inoperative position, there being means provided to maintain the out-going yarn in engagement with the periphery of the plate or disk and a clamping device for clamping the out-going yarn as it is severed for securing the yarn until the corresponding yarn feed finger is again moved into operative position.

It is another object of this invention to provide clamping and cutting means of the character last-described With means for removing the residual yarn ends from the clamping and cutting zone which means is embodied in a suction nozzle positioned closely adjacent the clamping means whereby, upon the clamping device being moved to release any residual yarn ends engaged thereby, they are drawn into the suction nozzle.

It is still another object of this invention to provide clamping and cutting means of the character described wherein an additional cutter blade is positioned on the periphery of said disk at a point more closely adjacent the knitting wave or stitch-forming zone than the point at which the first-mentioned cutter blade is positioned, with means for guiding the in-going yarn, extending from a yarn feed finger as it is lowered into operative position, to the cutter blade to thereby provide a relatively short yarn tail projecting from the fabric being knitted and thus requiring a lesser length of yarn to effect the cutting operation upon a yarn feed finger initially moving into operative position than is the case when only the single cutter blade is used.

Some of the objects of the invention having been stated, other objects will appear as the description proceeds when taken in connection with the accompanying drawings, in which- FIGURE 1 is a fragmentary side elevation of the upper portion of a circular knitting machine showing the needle cylinder, sinker head and other parts in section with the improved yarn clamping and cutting means and the residual yarn clearer applied thereto and other parts being shown somewhat schematically;

FIGURE 2 is a somewhat schematic, fragmentary perspective view showing in broken lines, the path of the yarn to the primary cutting means as the corresponding yarn feed finger is raised to inoperative position;

FIGURE 3 is an enlarged plan view of the structure shown in FIGURE 1, omitting the upper portion of the dial mechanism and with parts of the yarn end clearer tube broken away and in section;

FIGURE 4 is an enlarged view of the lower portion of the dial mechanism shown in the central portion of FIG-' URE l, omitting the yarn end clearer, the needle cylinder and other associated parts;

FIGURE 5 is a fragmentary vertical sectional view taken substantially along line 5-5 in FIGURE 3;

FIGURE 6 is an enlarged fragmentary vertical sectional View taken substantially along line 6-6 in FI URE 3, showing how the yarn is severed at the corresponding cutter blade;

FIGURE 7 is a perspective view similar to FIGURE 2 showing one of the yarn feed fingers just as it is lowered to operative position and showing, in broken lines, the path of the yarn to the first cutter blade for severing the in-going yarn adjacent the needles. I i

FIGURE 8 is an enlarged detail of the clamping device taken substantially along line 8-8 in FIGURE 3;

FIGURE 9 is an enlarged detail of the in-going or auxiliary cutter blade and corresponding yarn leader guide taken substantially along line 9-9 in FIGURE 3;

FIGURE 10 is an enlarged fragmentary view of the outgoing or primary cutter blade and the corresponding yarn leader guide taken substantially along line 1l-10 in FIGURE 3;

FIGURE 11 (Sheet 1) is a fragmentary detail taken 'susbtantially along line 11-11 in FIGURE 3.

The improved yarn severing and clamping means are shown in association with a knitting machine substantially of the type disclosed in Scott Patent No. 1,152,850 of September 7, 1915, and equipped with a dial mechanism of a type substantially as shown in Scott Patent No. 1,641,101 of August 30, 1927. However, it is to be distinctly understood that the improved clamping and cutting means may be readily adapted for use on any type of circular knitting machine provided with a rotary needle cylinder and which is capable of use with a plate positioned closely above and within a circular series of needles, Also, although a dial mechanism is disclosed herein, it is to be distinctly understood that the dial mechanism may be omitted and a suitable clamp and cutter plate or disk may be substituted for the stationary dial cam cap disclosed herein without departing from the spirit of the invention.

Referring more specifically to the drawings, the numeral indicates a conventional needle cylinder which may be driven by conventional means to, at times, rotate and to, at other times, reciprocate and which is provided with a circular series of independently vertically movable needles 11 which work in the usual grooves provided in the periphery of the needle cylinder 10. A sinker head 12 encircles the upper portion of the needle cylinder 1% and is provided with conventional sinkers or web holders 13 which cooperate with the needles in drawing stitches.

A conventional latch ring 15 encircles the upper ends of raised needles and is provided with the usual gap in which a throat plate i6 is positioned for supporting the free ends of yarn feed fingers or yarn feeding devices 17 when any one or more of the yarn feed fingers 17 are in lowered or operative position for feeding yarn Y to the needles.

In this instance, four yarn feed fingers are shown which define a yarn feeding station. In FIGURES 2 and 7 a few of the cylinder needles 11 are shown in lowered positions relative to other needles to define a knitting or stitch forming station or zone A which is also identified in FIGURE 3. The front end of the latch ring 15 rests upon the usual pedestal 2t and a post 21 is provided at the rear portion of the machine for pivotally supporting the rear end of the latch ring 15, as at 22.

The yarn feed fingers 17 are pivotally supported, as at 23, on an upwardly projecting inverted U-shaped portion 25 of the latch ring 15 and the yarn feed fingers 17 are controlled in the usual manner by a main pattern drum 25. The yarns Y are guided from a suitable source, not shown, to the yarn feed fingers 17 by a yarn guide plate 27 provided with a plurality of holes or apertures 30 (FIGURES 1 and 3) through which the yarns Y pass to the yarn feed fingers 17. The yarn guide plate 27 is suitably supported upon the inverted U-shaped portion 25 at the rear portion of the latch ring 15.

In the present instance, the knitting machine is provided with a dial mechanism, broadly designated at 35, which includes a stationary dial cam cap 36 spaced above the level of the sinkers 13, substantially axially alined with the needle cylinder it and encircled by the needles 11 while in raised position. The dial cam cap is shown in the form of a disk in FIGURES 2, 3 and 7 and may also be termed as a clamp and cutter plate or disk since, as heretofore stated, the improved yarn clamping and cutting means may be used with circular knitting machines which are not provided with a dial mechanism.

The dial cam cap or clamp and cutter plate 36 is provided with an upwardly projecting hub 37 which is fixed on the lower portion of a stationary bracket 40 which extends outwardly or forwardly in FIGURE 1 and is suitably secured to the latch ring 15. A shaft 41 is journaled in the bracket 40 and extends through the hub 37 and the disk 36 and has a conventional dial 42 secured thereto for rotation therewith, The dial 42 supports the usual dial needles and bits generally designated at 43 (FIGURE 8). The dial needles and bits are not shown in detail in the present drawings since they are conventional, they are shown in said Patent No. 1,641,- 101 and they do not constitute parts of the present invention. The dial i2 and associated needles and bits 43 are shown herein merely to enhance the utility of the present invention in severing yarn closely adjacent the needles whether they be dial needles or cylinder needles. The shaft ll has a gear 45 fixed on its upper end which meshes with conventional gearing, not shown, for driving the dial 4-2 and the dial needles and bits 43.

Now, in order to sever the out-going and in-going yarn as any one or more of the yarn feed fingers 17 are raised to inoperative position and lowered to operative position, respectively, the disk 36 is preferably provided with a smooth uninterrupted peripheral edge 5% in which first and second radially outwardly projecting cutter blades 51, 52 are positioned. The second cutter blade 52 may be termed as a primary cutter blade and the first cutter blade may be termed as an auxiliary cutter blade since the latter cutter blade may be omitted and is, thus, auxiliary to the primary cutter blade 52.

It will be noted that the cutter blade 51 is positioned above and immediately subsequent to the knitting point A, that is, the point at which the needles are drawn downwardly by conventional means, not shown, to draw stitches, whereby, immediately following the formation of stitches with the introduction of a new yarn to the needles by any one of the yarn feed fingers 17, the cutter blade 5'}; is engaged by the then iii-going yarn to sever the same as will be more fully described hereinafter. On the other hand, the primary or second blade 52 is spaced circularly from the first or auxiliary blade 51 so it is disposed somewhat opposite or in substantially spaced relation to the yarn feed fingers 17.

In order to lead the yarn to the respective cutter blades 51, 52 at the proper times, the blades 51, 52 are provided with respective elongated relatively thin yarn leader guides or blade shields 54, 55 which conform generally to the curvature of the arcuate or peripheral surface 58 of the plate as and whose ends nearest the yarn feed station are spaced slightly from the periphery 56 of the disk 36, but whose other ends are provided with respective thickened portions 56, 57 thereon (FIGURES 9 and 10) which are suitably secured to the periphery 59 of the disk 36. The outer surfaces of the yarn leader guides 54. 55 are preferably substantially flush with the outer surfaces of the respective blades 51, 52 and the leader guides 54, 55 are provided with respective longitudinally extending slots 6t 61 in medial portions thereof in which sharp outer portions of the respective blades 51, 52 are positioned.

The upper peripheral edge of the disk 36 is preferably provided with a groove 63 therein and in order to insure that the yarn is directed between the yarn leaders 54, 55' and the peripheral surface Sil of the disk 36, the free rear end of the leader guide 54; that is, the end thereof nearest the yarn feed fingers 17, has an upwardly and inwardly bent tongue 64- thereon which curves inwardly over the shoulder formed by the groove 63 in the periphery of the disk 31. The free rear end of the leader guide 55 also has an upwardly curving tongue 65 thereon which pref-- erably terminates on a level slightly above the shoulderformed by the groove 63, but which need not curve inwardly as does the tongue 64 on the leader guide 54..

By referring to FIGURE 2, it will be observed that the tongue 64 on the leader guide 54 is so positioned that, upon any one or more of the yarn feed fingers 17 being raised from operative to inoperative position, the yarn end extending therefrom or the out-going yarn, is held by the needles and drawn through the corresponding yarn feed finger or fingers l7 and passes outwardly of the curved tongue 64 and thus outwardly of the leader guide 54- spasms to subsequently engage the tongue 65 of the leader 55 to be deflected inwardly and severed by the cutter blade 52 in a manner to be later described. On the other hand, as any one or more of the yarn feed fingers 17 move downwardly from inoperative to operative position, the yarn lies across the upper surface of the plate 36 and across the needles immediately forwardly of the throat plate 16 so that, upon the yarn subsequently being taken by the leading needle to which it is directed, this needle will cause the yarn tail thus formed to pass beneath the inwardly curved upper endof the tongue 64 and, thus, the tongue 64 directs the yarn between the leader guide 5 and the surface 5% of the disk 36 to subsequently sever the yarn as shown in FIGURE 7.

Now, in order to clamp the yarn at the proper time and to also assist in guiding the yarn to the respective cutters or cutter blades 51, 5-2, a main clamp 74), an auxiliary or resilient clamp and clamp guide 71 and a yarn looping finger 72 are provided. The looping finger 7 2 is positioned closely adjacent the vertical plane of the knitting wave A; that is, subsequent to the yarn feeding station, and the auxiliary clamp and clamp guide 71 is positioned forwardly of the looping finger 72 while the main clamp 70 is positioned slightly forwardly of the auxiliary clamp and clamp guide 71. However, it will be noted that the clamps 70, 71 and the looping finger are positioned rearwardly of the front primary or second cutter blade 52 and in planes substantially midway between the yarn feeding station and the primary cutter blade 52. Also, it should be noted that the looping finger 72. is positioned rearwardly of the vertical plane of the cutter blade 51.

The main clamp 70 may be of any desired construction and is shown in the form of a substantially rectangular plate preferably made from a friction material such as plastic, Masonite, fiberboard, rubber or the like. The main clamp 70 is secured to one side of a substantially Z- shaped main clamp carrier lever 75, as by means of a clamp retaining plate 76 and screws or rivets 77. The lever 75 is oscillatably mounted, on a pin or screw 80, on one side of .the hub 37 of the clamp and cutter plate 36. The pivotal connection 80 for the lever 75 is shown in the form of a screw preferably surrounded by a compression spring 81 to frictionally retain the lever 75 on the screw8t).

The main clamp 70 normally bears against the upper surface of the clamp and cutter plate 36 and the end of the lever 75 remote from the main clamp 7t has the lower end of .a link 82 .pivotally connected thereto whose upper end is pivotally connected to the forward end of a control lever 83. The control lever 33 is pivotally mounted, as .at 84, on a projection 85 provided on the latch ring 5t} adjacent the hroat plate 16 and the forward end of the lever 83 is normally urged upwardly by any suitable means such as a compression spring 86 (FIGURE 3) whose upper end bears against the lower surface of the forward portion of the lever 83 and whose lower end is supported on a projection 87 projecting outwardly from the bracket 40.

The rear or outer end of the lever 83 is engaged by the upper end of a thrust rod 90 which, as best shown in FF- URE 1, extends downwardly and engages the periphery of the main pattern drum 26 or any one of a series of circulariy arranged cams provided thereon. Said series of cams includes a make-up cam 91, a clearer cam 92 and a plu rality of spaced operational cams of which there are four shown in FIGURE 1 indicated at 0-1, C-2, C3 and C4. All of the cams C4 to C4, inclusive, function in substantially the same manner and there may be a greater or lesser number of such operational cams provided depending upon the nature of the article being knitted.

Upon engagement by any one of the operational cams or-the-make-up cam 91, the thrust rod 90 moves upwardly to impart upward movement to the main clamp 79 to release any residual yarn ends therebeneath or to facilitate .the introduction of another yarn portion therebeneath.

On the other hand, the clearer cam 92 is relatively higher than the operational cams and the make-up cam '91 so as to raise the main clamp 70 relatively higher than the distance to which it is raised relative to the clamp and cutter plate 36 by any one of the operational cams or the makeup cam 91 and so that the auxiliary clamp and clamp guide is also raised therewith as will now be described.

The auxiliary clamp 71 is preferably made from spring steel or other resilient material and its free end is curved upwardly and overlies the groove 63. The inner end of the auxiliary clamp and clamp guide 71 is provided with a yarn-interrupting shoulder 93 and a tail portion 94 which is attached to the upper surface of the clamp and cutter plate or disk 36 by any suitable means, such as a screw 95 which screw is surrounded by a torsion spring 9d, one end of which is connected to the tail '54 of the auxiliary clamp and clamp guide 71. The other end of the torsion spring 96 forms the body of the yarn looping finger 72. The shoulder '93 retains the out-going yarn portion in alinement with a suction nozzle 1M and the main clamp 74 At the juncture of the tail portion '94 with the body of the auxiliary clamp 71, a slotted member 7 in the form of an inverted U-shaped member is provided which projects upwardly therefrom and is loosely penetrated by one of the screws or rivets 77 heretofore described (FIGURE 8). The slotted guide or inverted U-shaped member 97 is so arranged that the pin, rivet or screw 77 will not engage the same until the main clamp 7t? has been moved upwardly a predetermined distance, which distance is substantially equal to the distance that it is raised by any one of the operational cams C-l through C-4 or the make-up earn 91. However, upon the clearer cam 92 moving into engagement with the thrust rod 9% (FIGURE 1), the clamp 79 is then moved upwardly to where the screw, pin or rivet will engage the upper portion of the inverted U-shaped member 97 (FIGURE 8) to thereby impart upward movement to the resilient auxiliary clamp and clamp guide 71 to also release any residual yarn disposed therebeneath.

It will be noted in FIGURES l and 3 that the open lower end or orifice of a suction clearer or nozzle 101 is positioned closely above the upper surface of the disk 36 and adjacent the main clamp 70. The nozzle 101 is preferably oval-shaped as shown in FIGURE 3 and is also disposed immediately above the paths of any yarns which extend from corresponding yarn feed fingers 17 to the primary cutter blade 52. The nozzle 1431 extends upwardly and is integral with or attached to a conduit or tube 192 which extends reaiwardly and is suitably attached, as by a bracket 103 and a screw 194 to the bridging upper portion of the inverted U-shaped projection 25 on the latch ring 15. The rear end of the conduit 1&2 is connected to another conduit 105 which leads to a col lecting device 106 having a foraminated wall 107 which is communicatively connected with a suitable source of suction shown schematically and indicated at 116 in FIG- URE 1. Thus, any residual yarns released from the clamps 7Q, '71 are sucked into the nozzle 161 and carried to the collecting chamber 106, thus maintaining the clamping and cutting zone clear of residual yarn end portions.

Method of operation Now, when a new article is to be knit, the make-up cam 91 engages the thrust rod 90 to raise the clamp 7% to an intermediate position. At this time, a yarn norm-ally extends from each of the yarn feed fingers Y over the yarn looping finger 72 and is lightly clamped against the upper surface of the disk 36 by the auxiliary clamp 71. Of course, if this is not the case, the yarn end is manually inserted under the resilient auxiliary clamp 71. Assuming that the yarn feed fingers 17 are then in raised position, any one or more of the yarn feed fingers move downwardly to operative position to thus feed the corresponding yarn to the needles, including either needles 7 11 carried by the needle cylinder 1% or both the needles 11 and the bits-and-needles 43 carried by both the needle cylinder 10 and the dial 42.

The initial or leading needle which takes the yarn in the hook thereof then moves with rotation of the dial and needle cylinder and loops the yarn then extending therefrom to the auxiliary clamp 71 over and then under the yarn looping finger 72. This causes the yarn to ex tend from the yarn looping finger '72 at such an angle as to pass beneath the tongue 64 on the free end of the yarn leader guide 54. The said leading needle or initial needle then forms a stitch from the yarn directed thereto at zone A as to subsequent needles and, with continued movement of said initial needle in a counterclockwise direction in FIGURE 7, the yarn is moved forwardly between the leader guide 54 and the peripheral surface 59 of the disk 36.

in so doing, the yarn is tensioned because of its being clmped by the auxiliary clamp 71 which causes the instant yarn end to apply pressure against the rear surface or" the loop forming finger 72 to bias the same forwardly as shown in broken lines in FIGURE 7. As the loop forming finger 72 is biased forwardly, the yarn end then moves into engagement with the blade 51 which then cooperates with the walls of the slot 60 in the leader guide 54 to sever the yarn, thus providing a relatively short yarn tail projecting from the fabric being knit, which yarn tail may be as little as from three-eighths of an inch to onehalf an inch long.

The cam 91 may move out of engagement with the thrust rod 99 (FIGURE 1) before the in-going yarn end is actually severed, in which instance, the main clamp 70 will also assist in clamping the corresponding yarn end against the upper surface of the disk 36 during the severing of the ingoing yarn end. This leaves a corresponding residual yarn portion which is lightly clamped against the clamp and cutter plate or disk 36 by the auxiliary clamp 7i. and which is tightly clamped against the plate 36 by the main clamp 76 as the makeup cam 9i moves out of engagement with the lower end of the thrust rod 93*.

Upon a predetermined portion of fabric then being knit, such as a welt or hem or any other portion thereof and following which a yarn change is required, a cam such as cam C-1 engages the thrust rod 95 to raise the main clamp 7%) to an intermediate position as heretofore described. A this time, one or more of the previously lowered yarn feed fingers 17 are raised and it will be observed in FIGURE 2 that the out-going yarn end initially extends, from any raised yarn feed finger 17 to the last needle to which it was fed, so as to subsequently clear or pass outwardly of the leader guide 54- of the first cutter blade 51 and over the looping finger 72. This is necessary ot insure that the yarn is clamped before it is severed. Since the upwardly curving free end or outer end of the auxiliary clamp extends outwardly beyond the edge of the disk as, or at least, over the groove 63, as the end of the yarn attached to a needle moves past the leader guide 54, the yarn end passes beneath the auxiliary clamp 71 and then slides between the clamp 71 and the plate 36 as it is subsequently passed beneath the main clamp 70 which, as heretofore stated, is then in raised position.

At substantial the time that the yarn commences to pass beneath the main clamp 70, since the yarn is then moving against or in close proximity to the periphery 50 of the disk 36, the yarn is then engaged by the tongue 65 and directed between the peripheral surface 5%) of disk 36 and the leader 55. It is apparent that with further movement of the needle cylinder, the out-going yarn portion is then severed by the blade 52, as shown in FIG- URE 6, closely adjacent the needles. After the out-going yarn end has been severed by the cutter blade 52,, the cam, such as cam C-l, moves out of engagement with the thrust rod 90 so the spring 86 (FIGURE 3) then returns the main clamp 7b to operative position.

In the meantime, that portion of the yarn which extended from the main clamp 76) to the cutter blade 52 is sucked into the suction nozzle 1&1, but does not pass into the pipe or conduit m2, because the yarn still extends through the corresponding y-arn feed finger. It is apparent that, during the knitting of an article, before any one of the yarn feed fingers 17 is raised to inoperative position, another of the yarn feed fingers 17 is lowered irito operative position or another previously lowered yarn feed finger 17 remains in lowered or operative position. Assuming that a yarn feed finger is lowered into operative position after its yarnend has been severed by the second or primary blade 52, it is apparent that the yarn leading from the lowered yarn feed finger is looped around the yarn looping finger 72 and severed by the blade 51 in the manner heretofore described to thereby form a residual yarn portion. This may occur as each successive operational cam C-1, C-2, C-3 move into engagement with the lower end of thrust rod 93' so that, ultimately, a substantial number of loose residual yarn portions may be clamped beneath the main clamp 70 and the auxiliary clamp 71.

The clearer cam 92 then engages the lower end of the thrust rod and raises the main clamp '70 so that it, in turn, raises the auxiliary clamp 75 to thereby release all of said residual yarn portions from the clamps so they may be sucked into the nozzle 131 and carried along the conduits 1% and to the collecting box or chamber 1%. When both of the clamps 7b, 71 are raised in the manner last described, the yarns do not withdraw from any inactive yarn feed fingers since the free ends thereof are also drawn into the nozzle 101 with sufiicient force to Prevent the yarns from being withdrawn through the eyes of any raised or inoperative yarn feed fingers. It is contemplated that the clamping means may be omitted and the suction nozzle ltlll utilized as the sole means of holding those yarn ends extending from the yarn feed fingers. Suificient tension is applied particularly to inactive yarns extending from inactive yarn feed fingers as well as the terminal portions of active yarns by suction in the nozzle 191 to control and maintain the disposition of the yarns over the dial cam cap when the yarn clamping means may be in the elevated position or omitted entirely.

Now, the first or auxiliary cutter blade and its corresponding leader guide 5'4 may be omitted but, in this instance, a greater length of residual yarn will remain as a result of immediately successive cutting operations by the blade 52 than is the case when succeeding yarn cutting operations are performed by the blades 52, 51. Also, it may happen that the portion of the yarn extending from blade 52 over finger 72 to a raised yarn feed finger 17 may be too short to permit the use of the same blade 52 for severing both the out-going and in-going yarn portions. in the absence of the auxiliary cutter blade 51 and the corresponding leader guide 54, upon any one or more of the yarn feed fingers 1'7 being lowered to operative position, the yarn then clamped beneath the clamps 70, '71 would be drawn downwardly and would be looped over and beneath the tensioning or yarn looping finger 72 as the cylinder moved in a counterclockwise direction in FIGURE 2 so that the yarn would then be severed by the second or primary blade 52. In this instance, the main clamp 79 should be raised so the yarn end may slide between the resilient auxiliary clamp 71 and the plate 36 during a portion of its travel with the cylinder needles or dial needles.

The main reason for providing the auxiliary cutter blade 51 and its corresponding yarn leader guide 54- is that, the length of the yarn from raised yarn feed fingers to the primary cutter blade 52, at the time the yarn is cut by the primary cutter blade 52, is such that, upon a yarn feed finger being lowered to operative position, it may happen that the corresponding yarn end will be completely withdrawn from beneath the clamps or will have parted between the clamps and the corresponding leading needle upon being taken by said leading needle in the cylinder or dial and by the time the corresponding needle has moved past the blade 52 sufficiently to cause the yarn extending therefrom to engage the blade 52. Since the yarn end would not then be under tension, it would often happen that the in-going yarn would not be severed by the blade 52 or it would not be severed sufficiently close to the needles.

'It has been found that, by providing the auxiliary cutter blade 51 and the corresponding yarn leader guide 54 adjacent the yarn feed fingers as shown in FIGURES l, 2, 3, 4 and 7, the auxiliary clamp 71 need not serve as a clamp and may merely rest lightly upon or be spaced a slight distance above the upper surface of the clamp and cutter plate 36 so that it merely serves as a yarn clamping guide to assist in guiding the out-going yarn beneath the then elevated main clamp 75. When the yarn becomes an in-going yarn with lowering of the corresponding yarn feed finger to operative position, the yarn is drawn beneath the tongue 64 and, thence, between the yarn leader guide 54 and the peripheral surface 5%) of the disk 36 and into engagement with the corresponding cutter blade 51 by the leading needle, while the yarn end portion remote from the cutter blade 51 is tightly clamped by the main clamp 7 J. The resiliency of the yarn looping finger 72 also compensates for any lack in the length of that portion of the yarn then extending from the main clamp 70 to the initial needle to which it is directed by the corresponding yarn feed finger.

It is thuse seen that I have provided improved simply constructed yarn clamping and cutting means which will insure that relatively short yarn tails of uniform length remain connected to or extending from the knitted fabric as compared to the length of such tails which have remained as a result of the use of the usual types of yarn clamping and cutting devices. This eliminates the clipping operation usually performed by inspectors so that, for example, an inspector can inspect as many as twohundred dozen of ladies seamless hose in a normal working .day. Heretofore, an inspector was capable of inspecting an average of only forty dozen seamless hose in a normal Working day because of the additional time required to detect and then sever or clip the yarn tails.

It is apparent that the length of the tails may be increased by raising the cutter blades 51, 52 relative to the needles such as by securing the cutter blades to the upper surface of the shoulder formed by the peripheral groove 63 in the disk 36. Also, in the absence of a .dial mechanism being used, the clamp and cutter plate need not be circular and only a segmental plate of sufiicient peripheral len th to accommodate the blades 51 and 52 and the corresponding yarn leader guides 54, 55 need be provided.

When the element 71 is used only as .a yarn clamping guide as opposed to a yarn clamp, it is apparent that, following each successive set of cutting operations by the cutter blades 52, 51, every time the main clamp 70 is raised, the resultant residual yarn portion is immediately carried away from the clamp and cutter plate 36 by the suction nozzle 191 so .that only a very few, if any, residual yarn portions remain on the clamping plate at any one time.

The auxiliary clamp 71 may serve in that capacity in some instances in order to accommodate various types of yarns, since the holding eifect of the nozzle 101 may not sufiice, in some instances, to hold the yarn sufiiciently taut when the main clamp 79 is raised. However, in knitting with rayon, light cotton, nylon and other synthetic yarns, the element '71 need only serve as a guide for guiding the out-going yarn beneath the clamp '76.

In the drawings and specifications there has been set forth a preferred embodiment of the invention and, although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being defined in the claims.

I claim:

1. The method of controlling yarn in a circular knitting machine having at least one rotary series of needles and movable yarn feeding means for etfecting multiple yarn changes in the course of knitting which includes severing each yarn within the needle circle in the course of each successive yarn change to form at least one loose residual yarn portion While creating suction currents adjacent the area in which each yarn is severed for withdrawing said residual yarn portion from said area.

A method of controlling yarn extending from a yarn feeding means to the needle circle of a circular knitting machine which comprises severing the yarn adjacent the needle circle and withdrawing and holding the free end extending from the yarn feeding means by a suction current.

3. The method of controlling yarn in a circular knitting machine having at least one rotary series of needles forming a needle circle and movable yarn feeding means for effecting multiple yarn changes in the course of knitting which includes severing a yarn involved in a yarn change to form at least one loose yarn portion within the needle circle and creating suction currents within the needle circle for withdrawing said yarn portion.

4. The method of controlling yarn in a circular knitting machine having at least one rotary series of needles and movable yarn feeding means for effecting multiple yarn changes during knitting for forming loose yarn portions which includes creating suction currents by pneumatic means adjacent said needles, positioning a yarn extending from the yarn feeding means in the path of said currents and severing the yarn to form a yarn portion whereby said yarn portion is withdrawn by said suction currents.

5. The method of controlling yarn in a circular knitting machine having circularly arranged rotary needles and having yarn feeding means movable into and out of operative position which comprises the steps of intro ducing yarn to the needles with the yarn feeding means in the operative position, forming a few stitches with the yarn, severing the yarn extending from the needle to which the yarn Was initially introduced closely adjacent to and within the needle circle, knitting a plurality of courses, moving the yarn feeding means 'to inoperative position, then again severing the yarn closely adjacent the needles within the needle ircle, and evacuating the severed yarns from within the needle circle.

6. The method of controlling yarn in a circular knitting machine having circularly arranged rotary needles and having yarn feeding means movable into and out of operative position which comprises the steps of introducing yarn to the needles with the yarn feeding means in the operative position, then forming a few stitches with the yarn, then severing the yarn extending from the needle to which the yarn was initially introduced closely adjacent to and within the needle circle, then knitting a plurality of courses, then moving the yarn feeding means to inoperative position, then again severing the yarn closely adjacent the needles within the needle circle, and then repeating :the series of steps as prescribed to result in at least one loose yarn portion while creating suction currents within the area formed by the circularly arranged rotary needles for carrying such yarn portions away from said area.

7. In the operation of a circular knitting machine having a rotary cylinder with independent needles, a dial cap mounted adjacent the top of said cylinder, and a group of individually retractable interchangeable yarn feeds, the method comprising the steps of applying tension to a yarn extending over said dial cap by suction, and manipulating said yarn while so tensioned.

8. In the operation of a circular knitting machine having a rotary cylinder with independent needles, a dial cap mounted adjacent the top of said cylinder, and at least one individually retractable yarn feeding finger, the method comprising the steps of applying tension to a yarn extending from said feeding finger over said dial cap by suction, and inserting said yarn into the needles for knitting while so tensioned.

9. In the operation of a circular knitting machine having a rotary cylinder with independent needles, a dial cap mounted adjacent the top of said cylinder, and a group of individually retractable interchangeable yarn feeds, the method comprising the steps of applying tension to a yarn extending over said dial cap by suction, and severing said yarn while so tensioned.

10. In the operation of a circular knitting machine having a rotary cylinder with independent needles, a dial cap mounted adjacent the top of said cylinder, and a group of individually retractable interchangeable yarn feeds, the method comprising the steps of tensioning by pneumatic means a yarn end extending from the needles over said dial cap, and severing said yarn end from the needles while so tensioned by guiding it into a yarn severing means.

11. In the operation of a circular knitting machine having a rotary cylinder with independent needles, a dial cap mounted adjacent the top of said cylinder, and a group of individually retractable interchangeable yarn feeds, the method comprising the steps of applying tension by suction to an inactive yarn extending from the yarn feeding means over said dial cap, inserting said yarn .While so tensioned into the needles for knitting, severing said yarn to form an unattached yarn end, and then removing the yarn end by means of said suction.

12. In the operation of a circular knitting machine having a rotary cylinder with independent needles, a dial cap mounted adjacent the top of said cylinder, and a group of individually retractable interchangeable yarn feeds, the method comprising the steps of Withdrawing a yarn from active knitting by retraction of one of said yarn feeds, whereby said yarn is carried by the last needle to knit it around said cylinder and above said dial cap, applying tension to said withdrawn yarn by suction, severing the withdrawn yarn within the needle circle and close to the fabric, and engaging the severed yarn end by means of said suction.

13. in the operation of a circular knitting machine having a rotary cylinder with independent needles, a dial cap mounted adjacent the top of said cylinder, a group of individually retractable interchangeable yarn feeds, and a yarn severing means disposed peripherally of said dial cap at a point angularly spaced from said yarn feed group in the direction of cylinder rotation, the method comprising the steps of applying tension by pneumatic means to an inactive yarn end extending over said dial cap at a point trailing said yarn feed group and leading said yarn severing means in the direction of cylinder rotation, inserting said inactive yarn into the needles for knitting, then withdrawing a yarn from active knitting by retraction of one of said yarn feeds, and shearing the inserted yarn to form an unattached yarn portion, and removing the yarn portion from above the dial cap by pneumatic means.

14. In the operation of a circular knitting machine having a rotary cylinder with a complement of needles, a retractable yarn feed, and a clamp Within the needle circle by which a yarn is held while the feed is retracted, the steps of causing the yarn, upon insertion of the feed, to be formed into a loop about an element adjacent the clamp within the needle circle, causing the yarn to be severed, upon completion of such loop, close to the first needle by which it was taken, and causing the clamp to be actuated to release the cut loop for removal from within the needle circle by suction means.

15. In the operation of a circular knitting machine having a rotary cylinder with a complement of needles, a retractable yarn feed, and a clamp within the needle circle by which a yarn is hold while the feed is retracted, the steps of causing the yarn, upon insertion of the feed, to be formed into a loop about an element adjacent the clamp within the needle circle, causing the yarn to be severed, upon completion of such loop, close to the first needle by which it was taken, causing the clamp to be actuated to release the cut loop, and finally applying suction to remove the loop from within the needle circle.

16. In a circular knitting machine having a rotary cylinder with independent needles, a dial cap mounted adjacent the top of said cylinder, and a group of individually retractable interchangeable yarn feeds, yarn tensioning means comprising a conduit having an opening spaced vertically above said dial cap at a point angularly spaced from said yarn feed group in the direction of cylinder rotation, and means for causing air flow through said conduit and into said opening during knitting.

17. In a circular knitting machine having a rotary cylinder with independent needles, a dial cap mounted adjacent the top of said cylinder, and a group of individually retractable interchangeable yarn feeds, yarn tensioning means comprising a conduit having an open end disposed above said dial cap at a point angularly spaced from said yarn feed group in the direction of cylinder rotation, means for inducing air flow into said open end during knitting, and yarn severing means disposed peripherally of said dial cap at a point angularly spaced from said group of yarn feeds in the direction of cylinder rotation.

18. In combination with a circular knitting machine having a plurality of yarn feed fingers, a plurality of needles lying in a circle and means for selectively moving the yarn feed fingers into and out of knitting relation with said needles, and pneumatic means Within the needle circle for Withdrawing and holding at least one free end of yarn extending from the yarn feed fingers.

19. in combination with a circular knitting machine having knitting instrumentalities including yarn feed fingers and needles lying in a circle, means for cutting the yarn extending from a yarn feed finger close to the knitted fabric at a point within said needle circle after a yarn feed finger is rendered inactive, and pneumatic means for transferring the cut yarn end extending from said yarn feed finger to a point remote from said needle circle whereby said transferring means will position the yarn of said feed finger in a generally predetermined position within the needle circle.

20. In combination with a circular knitting machine having a plurality of yam feed fingers, a plurality of needles lying in a circle and means for selectively moving the yarn feed fingers into and out of knitting relation with said needles, means within the needle circle for cutting inactive yarns extending from the yarn feed fingers, means comprising a suction device having an opening within the needle circle into which inactive yarn ends from said feed fingers pass whereby said yarn ends are positioned in a generally predetermined location within the needle circle, and means for creating movement of air into said opening.

21. In a circular knitting machine having a rotary cylinder with independent needles, a dial cap mounted adjacent the top of said cylinder, a group of individually retractable interchangeable yarn feed fingers and a timing drum controlling the movement of said yarn feed fingers, yarn tensioning means comprising a conduit having an open end disposed above said dial cap at a point angularly spaced from said yarn feed group in the direction of cylinder rotation, means for inducing air flow into said open end to tension and retain yarns from said yarn feed fingers, and means for releasably clamping yarn above said dial cap.

in: e.

22. A circular knitting machine having a circle of in dependent needles, yarn feeding means movable to inactive and active positions, yarn severing means positioned Within and adjacent the needle circle and angularly spaced from said yarn feeding means to sever a yarn being removed from knitting when the yarn feeding means is in the inactive position and to again sever said yarn when said yarn feeding means is in the active position to form a loose yarn portion within the needle circle, and yarn transferring means Within the needle circle for conveying said loose yarn portion from within the needle circle by pneumatic means.

23. A circular knitting machine having a circle of independent needles, yarn feeding means movable to inactive and active positions, yarn severing means positioned within and adjacent said needle circle and angularly spaced from said yarn feeding means in the direction of cylinder rotation to sever a yarn being removed from knitting when the yarn feeding means is in the inactive position and to again sever said yarn when said yarn feeding means is in the active position to form a loose yarn portion within the needle circle, and pneumatic means within the needle circle for removing said loose yarn portion.

24. A circular knitting machine having a circle of independent needles, yarn feeding means movable to inactive and active positions, yarn severing means positioned within and adjacent said needle circle and angularly spaced from said yarn feeding means in the direction of cylinder rotation to sever a yarn being removed from knitting when the yarn feeding means is in the inactive position and to again sever said yarn when said yarn feeding means is in the active position to form a loose yarn portion within the needle circle, and suction means within the needle circle for removing said loose yarn portion.

25. A circular knitting machine having a circle of independent needles, yarn feeding means movable to inactive and active positions, yarn severing means positioned within and adjacent said needle circle and angularly spaced from said yarn feeding means in the direction of cylinder rotation to sever a yarn being removed from knitting when the yarn feeding means is in the inactive position, and suction means within the needle circle for controlling and retaining said yarn.

26. A circular knitting machine having a circle of independent needles, yarn feeding means movable to inactive and active feeding positions, yarn severing means positioned within and adjacent said needle circle and angularly spaced from said yarn feeding means in the direction of cylinder rotation to sever a yarn being removed from knitting when the yarn feeding means is in the inactive position and to again sever said yarn when said yarn feeding means is in the active position to form a yarn feeding means.

27. In a circular knitting machine having a rotary cylinder with independent needles forming a needle circle, a dial cap mounted adjacent the top of said cylinder, and a retractable yarn feed finger, yarn tensioning and removal means comprising a conduit having an open end disposed above said dial cap within the needle circle at a point angularly spaced from said yarn feed in the direction of cylinder rotation, means for inducing air flow into said open end during knitting, and yarn severing means within and closely adjacent the needle circle.

28. In a circular knitting machine having a rotary cylinder with independent needles, a dial cap mounted adjacent the top of said cylinder, at least one retractable yarn feeding finger and yarn severing means disposed peripherally of said dial cap to sever yarn at a point angularly spaced from said finger in the direction of cylinder rotation, a yarn tensioning element mounted on the dial cap between the finger and the point of yarn severance over which the yarn is drawn by rotation of the cylinder following each retraction of the finger and about which, following each insertion of the finger, the yarn is looped incident to being brought to the point of yarn severance by rotation of the cylinder, and suction means for removing said severed yarn loop.

29. A circular knitting machine having a circle of independent needles, yarn feeding means movable to and from feeding position, yarn severing means positioned within and adjacent said needle circle and remote from said feeding means, said severing means being operative to sever yarn upon moving the feeding means from feeding position and to again sever the same upon subsequent moving of the feeding means to feeding position to produce a loose yarn end within the needle circle, and suction means for removing said loose end.

30. In a circular knitting machine having a rotary cylinder with independent needles, a dial cap mounted adjacent the top of said cylinder, and a group of individually retractable interchangeable yarn feeds, yarn tensioning means comprising a conduit having an open end disposed above said dial cap at a point angularly spaced from said yarn feed group in the direction of cylinder rotation, and means for inducing air flow into said open end.

References Cited in the file of this patent UNITED STATES PATENTS 2,269,757 Davis Jan. 13, 1942 2,375,473 Holmes et al. May 8, 1945 2,560,484 Schoenster et a1 July 10, 1951 

